Process of making mixed gas



Jan. 3, 1928. 1,654,942

H. NIELSEN ET AL PROCESS OF MAKING MIXED GAS Filed March 21. 1921 hi mam Patented Jan. 3, i928.

U ITE HARAL'D NIELSEN, OE IE SSWELL HILL, AND JAMES RANKIN GARRUW, F WIMBLE- I393 ENGLAND.

FROCESS OF MAKING MIXED GAS.

Application filed March 21, 1921, Serial No. 454,168, and in Great Britain February 23, 1920.

(GRANTED UNDER THE PROVISIONS OF AC? ()3? KABGH 3, 192L531 STAT. 13., 1313.)

low temperature distillation or carboniza tion by passing the gas from producers through retorts containing the material which is to be treated.

In methods ofthis kind the usual proposal has been to pass all the gases evolved by a. single producer through the low tem per .ture retort or retorts. In such cases the quantity of producer gas which it has been proposed to use being far in excess ofthe quantity actually required to effect low temperature distillation would result in the hydrocarbon vapors or retort gas evolved during treatment in the retort becoming mixed with an extremely large quantity of producer gas. Consequently, the recovery of the tar oils by condensation and of the permanent light hydrocarbon oils by ;oil washing would be extremely ditficult, while the oil washing plant required for the purpose would necessarily be of large dimensions and costly if constructed to treat the great volume of mixed gases thus produced, and it is the chief object of thepresent inven- 0 tion to overcome the d'iificulty of treating in tar oil condensers and in oil washers a mixture containing a large excess of producer as. g According to the present invention a multiplicity of gas producers are employed, one

of said producers being situated adjacent to the retort and being of such capacity or being supplied with a measured quantity of fuel which is such that the quantity of producer 40 gas which is evolved, while containing orpossessing sufiicientso-called sensible heat to effect the requisite heating of the carbonaceous material in the retort, will not unduly dilute the retort gas, the intermingled producer gas and retort gas after leaving the retortand after being treated so as to condense or remove the volatile oils contained therein, being mixed in a suitable receptacle, such as an ammonia scrubber, with pro ducer gases which are withdrawn from and passed directly into such receptacle from the auxiliary or supplementary gas producers. The semi-coke obtained from the retort which latter is preferably of the revolving type and preferably adapted to provide sufficient'coke for use in all the producers of the series is collected after treatment in a suitable'receptacle and a measured quantity of this material is employed to feed the pro ducerwhich is in communication with the retort, the quantity supplied being such as to generate in the producer only the requisite quantity of producer gas which is required for heating the material in the retort and the excess of retort coke being available to feed the supplementary producers of the series. Additionally, by reason of the degasification of the. coal at a-low'temperature, there is formed low temperature carbonization coke which is divided into two portions, each of which is completely gasified. The producer gases from the auxiliary producers (which gases contain ammonia but little or no tar oil vapors) are led as aforesaiddirect to the ammonia scrubbers where they meet the conibined roducer and retort gas obtained from the distillation of the carbonaceous material within the retort after said gases have passed through the condensers and oil washers. Owing to this arrangement, and as the gas produced from the auxiliary producers does not pass either through the retort or through the tar oil condensers and oil jwashers the mixed producer and distillation gases are not diluted until mixed with the auxiliary producer gas in the ammonia washers thus rendering the extraction in the condensers and washers of the oil vapors easier and less expensive than heretofore.

In order that the said ipvention may be i clearly understood and readily carried into effect the same will nowbe described more fully with reference to the accompanying drawing which shows a side elevation of the apparatus with parts in section of the invention for the purpose of clearness of illustration.

Referring to the drawing a is a hopper or container for the black coal, bituminous or otherwise, lignite, brown coal, peat or wood for feeding the retort or rotary drum 0, while i) is a feeding pipe by means of which the raw fuel in the hopper a is fed into the low temperature carbonization retort c, the pipe 6 also serving to conduct the mixed producer and distillation gases away from the retort. d is a fixed annular casing surrounding one end of the distilling or carbonreiori; 0 wherein csrhonized fuel linseed in reborn c is coliecied sill/er Eel;- ing through the opening a in the reiore u e is the carbonized fie, off-mire from the reiort c, sing observed lines the semi-coke drops from she fuel oiliake e inlo the hopper and f is a conveying plant of any well known cy, e iior conveying by means of chutes g ishe heated and partielly coked'rnarerial ind-s the overhead bunkers g'fro1n which it is fed into 'the gas producers p, 72 and h. h is the producer set apnri; for generating producer gas for use in heating the carbonaceous material in the retort- 0, while ,4), p

= and p are the auxiliary gesproducers. The

producer gas may be made iron"; alone or else 53min an and seesin. so as to produce in the latter case scrolled semi-water gas. 1)

is the pipe for admiiizing air to the producer h, and o is ishe pipe for admittin steam. 2' is a pipe for conducting the gas .L cm the producer :5 into the reiori; 0, both of said pipes Z1 and 2 passing through stufing boxes in at each end of the retorl; c. j is a cooler or condenser for inc m'med gases which leave the retort c, and 7c is an absorption apparatus for the recovery from said mixed gases or" condensable and absorbeble hydrocarbon products contained therein; A pipe 3 con ducts fiche stripped gases from the absorption apparatus is to an ammouis absorber m which letter also deals with the ammonia obtained in she auxiliary gas producers p, 32 p Branch pipes a carry the producer gas directly from the auxiliary gas producers p, 2 p to gas main n which is also connected in the absorber m so that all the gases produced from all four producers as also from' the retor'i: 0 are eventually mixed or united therein and from which che gases are conducted by means of outlet pipe 1* to further cleaning apparatus if so desired.

ji i'l order to prevent the raw material from adhering to the walls-of the retort o whilst undergoing heat treatment a certain amount of dry material may be introduced along with the raw material or crude fuel, or scrapers or similar devices of any well known type may be employed to keep the walls clear or to facilitate the movement of the raw material undergoing treatment through the retort.

If desired, the heated and partially coked material, which. is delivered from the fuel off-take e to the hopper 25, instead. of being conducted to the bunkers, may be removed from the hopper in its semi-coked condition.

The arrows shown on the drawing indicate the direction of flow of the gases as also that of the material under treatment.

It will thus be seen um an apparatus cons" acted according to the present invention provides a continuous method for the production of solid and gaseous fuel wish y-produci recovery without undue dilution neeaeee of the distillation gases from the carbonizing retort. It will thus be soon that by the prcsenb method three distinct combustible gases are produced having different characteristics and heating values, said method consisting in conducting raw carbonaceous material through a rotating low temperature retortoI" sufilcienl capacity to provide the coke-necessary for use in a nulltiplicity of gas producers and through which a thin layer of carbonaceous material is fed continuously, delivering the semi-coke produced in the retort into :1 series oi gas producers where it is, fully ga ified, and, in cases where air only is admitted To the gas producers, produces a heating gas of a specific hearing value, namely, 150 B. t. u. per cubic foot; passing the gas generated in one of said producers into said retort, withdrawing the mixed producer and distillation gases from ihe retort; condensing, vashing or otherwise removing the volatile oils ihereiroru and thereby producing a mixed gas of a higher heatingvalue, namely, 250 B. t. u. per cubic foot; passing the said mixed gas into a receptacle, and conducting directly into said receptacle che producer gas from the other said gas producers so as to mix the some with ithe treated gases from the retorr, thereby producin a thirdgas also of a different heating vs ue, namely, 175 ie 180 B. s. u, per cubic foot. In cases where air and steam are admitted to the producers so as to produce so-called water gas the heating value of the gas obiained from the producers is 300 B. t. 12. per cubic foot; that of the mixed gas obtained after the oils are ex tracted 400 B. t. u. and, after admixture with the semi-water gas, 350 B. t. 11. per cubic foot.

What we claim and desire to secure by Letters Patent of the United States is 1. A process of making mixed gas with by-product recovery from solid carbonaceous materials, which consists in conducting the raw fuel into a rotating low temperature retort of sufiicieni capacity to provide the coke necessary for use in a plurality of gas producers, and through which retort a relatively thin layer of carbonaceous fuel is fed continuously, carbonizing the fuel with hot producer gas, delivering the coke carbonized in the retort into a series of gas producers, one of said producers being in communication withthe retort, generating producer gas by blasting the coke in said producer with an aeriforrn or gascous fluid, passin the hot gas from said producer into said retort and thereby disfilling the fuel, withdrawing the mixed prodimer and distillation gases irom'the retort, condensing, washing or otherwisdzremoving the volatile oils from the mixed g ses, pass ing the said gases into a receptacle, and conducting diieeclv into said recep'acle the producer gas from another of said gas producers so as to mix the same with the treated distillation gases from the retort.

A method of making mixed coal gas and producer gas, which comprises degasifieatlon of coal at a low temperature/by hot wodueer gee, theiiehy forming low temperal= e -arhonizgu'tioncoke, dividing said coke in o two portions, completely gasiiying. one portion by blasting with an aerifori'h or gaseous fluid. passing the generated producer into direct Contact with the coalto heat the latter to produoe'the low temperature carboniZutic-n coke :1 "id coal gas, completely gasifyiog the second portion of the coke by I 'Wlill an aerifoi'm or gaseous fluid n1 producer gas. and mixing the gas produced from the first portion of the coke with the; from the second portion.

3-. A method of making mixed coal gas and produeer gas, which comprises degasification of the coal at a low temperature by hot producer gas, thereby forming low tem perature carbonization coke, dividing said coke into two portions, completely gasifying one portion by blasting with an aeriform or gaseous fluid, passing the generated producer gas into direct contact with the coal to heat the latter to produce the low temperature carhonization coke and coal gas, completely gas'ifying the second portion of the coke by blasting with an aeriform or gaseous fluid to form producer gas, mixing the gas from the first portion of the coke with that from the second portion, and so dividing the low temperature coke that the gas produced by the complete gasification of the first portion will produce sufiicient heat to cause low temperature degasification of a mass of coal equal to the original mass.

HARALD NIELSEN. JAMES RANKIN GARROW. 

